On Window Resize Event - windows

Question

The Problem
Call a procedure whenever the Main Excel Window is resized.
First attempt:
Sub Workbook_WindowResize(ByVal Wn As Window)
Debug.Print Wn.Width & "x" & Wn.Height
End Sub
Results:
The sub routine is called whenever the 'inner' workbook window is resized but not when the application window is resized. I.E. occcurs on resize of the Multiple Document Interface child containing the application instance.
Second attempt
Dim WithEvents App As Application
Private Sub App_WindowResize(ByVal Wb As Workbook, ByVal Wn As Window)
Debug.Print Wn.Width & "x" & Wn.Height
End Sub
Results:
Oddly, the same thing that happened before occurs, which definitely surprised me. The event only occurs when the workbook window is resized instead of the application window.
For this reason I started looking into using the windows API.
There are many examples of setting SystemWide keyboard and mouse hooks using the windows APIs. This is along the same lines:
Public Enum enHookTypes
WH_CALLWNDPROC = 4
WH_CALLWNDPROCRET = 12
WH_CBT = 5
WH_DEBUG = 9
WH_FOREGROUNDIDLE = 11
WH_GETMESSAGE = 3
WH_HARDWARE = 8
WH_JOURNALPLAYBACK = 1
WH_JOURNALRECORD = 0
WH_MOUSE = 7
WH_MSGFILTER = (-1)
WH_SHELL = 10
WH_SYSMSGFILTER = 6
WH_KEYBOARD_LL = 13
WH_MOUSE_LL = 14
WH_KEYBOARD = 2
End Enum
Private Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As LongPtr, ByVal lpfn As Long, ByVal hMod As Long, ByVal dwThreadId As Long) As LongPtr
Private Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Private Declare Function GetLastError Lib "kernel32" () As Long
'Ensure that your hook procedure does not interfere with the normal operation of other hook procedures
Private Declare Function CallNextHookEx Lib "user32" (ByVal hHook As Long, ByVal ncode As Long, ByVal wParam As Long, lParam As Any) As Long
Public hndl As Long
Sub HookWindow()
hndl = SetWindowsHookEx(WH_CALLWNDPROC, AddressOf measureWindow, Application.Hinstance, 0&)
Debug.Print hndl & "~~" & GetLastError()
End Sub
Sub unhookWindow()
ret = UnhookWindowsHookEx(hndl)
Debug.Print ret
End Sub
Public Sub measureWindow(code As Long, wParam As Long, lParam As Long)
If code > 0 Then
Debug.Print ThisWorkbook.Windows(1).Width & "x" & ThisWorkbook.Windows(1).Height
Else
ret = CallNextHookEx(measureWindow, code, wParam, lParam)
End If
End Sub
Results:
If I replace the WH_CALLWNDPROC in:
hndl = SetWindowsHookEx(WH_CALLWNDPROC, AddressOf measureWindow, Application.Hinstance, 0&)
with WH_KEYBOARD_LL the sub-routine is called whenever a key is pressed. Similarly, if I replace it with WH_MOUSE_LL the sub-routine is called whenever the mouse is moved or a mouse button pressed.
The problem is that when I try to hook the sub-routine to WH_CALLWNDPROC nothing happens?
Why?
I'm still not sure, but the same is true for all ENUMS in enHookTypes except WH_MOUSE_LL and WH_KEYBOARD_LL. Looking through the WinAPI documentation I read that you can use GetLastError from Kernel32.dll do get some indication of why the operation failed.
The error numbers I have got so far are (in decimal) error 5 (for JOURNAL hooks) and error 1428 for the rest.
Ultimately this also failed.

Answer 1

Application.Windows is a collection of window objects of Worbooks opened within the Application. The WindowResize event is raised when a non-maximized window changes size. The Workbook_WindowResize(ByVal Wn As Window) is exposed within the workbook object itself. The Application_WindowResize(ByVal Wb as Workbook, ByVal Wn As Window) event has to do with ANY/ALL of the workbooks within the Application when a non-maximized workbook's window changes size. Hence the difference in references passed in by the events. It is just a Window in the first case, of the workbook that raised the event, within the workbook object, and there is no question here which window it is (it's the "Me" workbook's window). It is both the Workbook and that workbook's window when it is raised at the Application level since the workbook the event relates to needs identification :) And no, Excel does not have a "Resize" event for the App window itself and you would need to go to APIs for that.
With the later Excel versions (past the 2010), there is ONE workbook per Excel Application window, the workbook's window is always maximized in the old sense, and both Workbook and Application events refer to the same workbook and would work just as you would want them to.

Answer 2

Solution , create a timer event that checks and compares the width every few seconds...
Sub my_ONTIME()
application.OnTime Now + TimeValue("00:00:2"), "my_TIMEREVENT"
End Sub
Sub my_TIMEREVENT()
If application.Width <> EWIDTHR Then ESCREENRESIZE
my_ONTIME
End Sub
Sub ESCREENRESIZE()
Dim EWIDTH As Single
Dim ESIDE As Single
Dim EMID As Single
EWIDTH = application.Width
EWIDTHR = EWIDTH
If EWIDTH < 500 Then
EWIDTH = 500
application.Width = 500
End If
EMID = 80 * 5.41
ESIDE = ((EWIDTH - EMID) / 2) / 5.41
Sheet1.Columns("A:A").ColumnWidth = ESIDE
Sheet1.Columns("C:C").ColumnWidth = ESIDE
End Sub